Cyclohexapeptide

Abstract

The present invention relates to a novel cyclohexapeptide, to a method for the preparation of said cyclohexapeptide and to the use of said cyclohexapeptide.

The invention claimed is: 
     
       1. A compound of general formula (1) or a salt thereof: 
       
         
           
           
               
               
           
         
         wherein R is hydroxyl. 
       
     
     
       2. The compound of  claim 1 , wherein the salt of the compound of formula (1) is a pharmaceutically acceptable salt. 
     
     
       3. The compound of  claim 2 , wherein the pharmaceutically acceptable salt is an acid addition salt with an organic acid comprising at least one organic acid selected from the group consisting of acetic, citric, glutamic, lactic, maleic, malic, oxalic, pamoic, propionic, succinic and tartaric acid. 
     
     
       4. The compound of  claim 2 , wherein the pharmaceutically acceptable salt is a diacetate. 
     
     
       5. A composition comprising caspofungin hydroxylamine or a salt thereof and a compound of general formula (1): 
       
         
           
           
               
               
           
         
         wherein R is hydrogen. 
       
     
     
       6. The composition according to  claim 5 , wherein the caspofungin hydroxylamine or a salt thereof is present in the composition in an amount of 0.01% to 2% based on weight. 
     
     
       7. A method for the preparation of a compound according to  claim 1  comprising contacting caspofungin or a salt thereof with an oxidizing agent. 
     
     
       8. The method according to  claim 7  further comprising purifying the compound by chromatography and isolating the compound. 
     
     
       9. The method according to  claim 7 , wherein the oxidizing agent is a peroxyacid. 
     
     
       10. The method according to  claim 9 , wherein the peroxyacid is at least one selected from the group consisting of m-chloroperoxybenzoic acid, peracetic acid, peroxymonosulphuric acid and peroxyphosphonic acid. 
     
     
       11. An antifungal medicament which comprises an antifungal effective amount of the compound according to  claim 1  as an antifungal agent. 
     
     
       12. A method for determining quality of a caspofungin sample which comprises analyzing the caspofungin sample for trace amounts of the caspofungin hydroxylamine using the compound of  claim 1  as a reference.